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Increasing evidence shows the positive effect of physical activity (PA) on maintaining cognitive function. Both processes seem intrinsically linked to each other. The most likely mechanism is a reciprocal stimulation of neuroplasticity. Based on extensive experimental work on animals and humans, the concept of an enriched environment, including PA and challenging cognitive tasks, has provided the basis to systematically assess possible interventions for successful aging. I will use recent findings on brain mechanisms associated with PA and its effects on higher cognitive function at a systems and molecular level to demonstrate the need to design effective interventions. Such interventions should be designed to take advantage of the presumed compensatory mechanisms of elderly individuals, thereby limiting functional decline in higher cognitive performance in aging people. My review of the most recent relevant publications concerning this topic supports the notion that it is a promising approach to provide cognitive training and PA in conjunction, since the combination may generate synergistic beneficial changes than either one individually. Multimodal training programs should therefore be tested. However, at present there is insufficient evidence to conclude that multimodal interventions are superior to isolated cognitive or physical exercise interventions, since major studies addressing this topic are lacking. These studies are needed to conclusively prove that both strategies will positively interact when used in combined interventions. Finally the use of modern technology for these interventions will be discussed.  相似文献   
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Can a society’s overall level of happiness change? Until recently, it was widely held that happiness fluctuates around set-points, so that neither individuals nor societies can lastingly increase their happiness. However, data from surveys carried out in Russia from 1982 to 2011 show that happiness fell substantially following the collapse of the Soviet Union, and has begun to rise again only recently. Additional data sources, including suicide rates and indices of negative affect expression, confirm these shifts. Contrary to set-point theory, we find that the recent increase has been driven as much by generational replacement as by mean reversion among individuals. The collapse of communism led to a permanent drop in subjective wellbeing among mid-life cohorts that was subsequently never fully recovered. Happiness can be substantially and permanently impacted by life-events, including those affecting society as a whole, and societal-level happiness can rise or fall over time as a result.  相似文献   
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Assessment of risk is one of the key issues in the field of responsible conduct of research which covers discourses of research ethics and research integrity. The principle of minimizing risks and balancing of risks and benefits is one of the main requirements of research ethics. In addition, the content of informed consent that is another fundamental principle of research ethics derives from the assessment of risks and benefits related to a particular research project. Risk assessment also plays a crucial role in methodological design of the research project. This is an important point where research ethics and research integrity discourses overlap. Firstly, because the choice of a control group (e.g., placebo control) is a key ethical issue related to the protection of the research subjects' interests. Secondly, because the quality of the research data, that is one of the key elements of research integrity, is closely connected to the choice of research methodology as well. The problem of biased interpretation or manipulation of risk related features of biomedical research should also be taken into account. Despite the importance of the concept of risk to the field of biomedical research, its relevance has not yet attracted a sufficient attention in the responsible conduct of research debate.  相似文献   
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An honor code is certainly a good place to start teaching engineering students about ethics, but teaching students to live honorably requires far more effort than memorizing a code of ethics statement or applying it just to academic performance. In the School of Engineering at Grand Valley State University, we have followed the model provided by the United States Military Academy at West Point. For our students this involves an introduction to the Honor Code as part of a larger Honor Concept at the very beginning of their studies and then making it an integral part of their preparation as engineers. The challenge is significant because the culture at large does not support living with an Honor Concept. This paper will begin with a discussion of the cultural context in which we must teach, because that context has changed significantly in the years since many faculty members were students themselves. The rest of the paper will detail the approach that we have taken to teach ethics as an engineer’s way of life. “The shortest and surest way to live with honor in the world is to be in reality what we would appear to be. All human virtues increase and strengthen themselves by the practice and experience of them.” Plato An earlier version of this paper was presented at the 2005 conference, Ethics and Social Responsibility in Engineering and Technology, Linking Workplace Ethics and Education, co-hosted by Gonzaga University and Loyola Marymount University, Los Angeles, CA, USA, 9–10 June 2005.  相似文献   
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The priority heuristic: making choices without trade-offs   总被引:9,自引:0,他引:9  
Bernoulli's framework of expected utility serves as a model for various psychological processes, including motivation, moral sense, attitudes, and decision making. To account for evidence at variance with expected utility, the authors generalize the framework of fast and frugal heuristics from inferences to preferences. The priority heuristic predicts (a) the Allais paradox, (b) risk aversion for gains if probabilities are high, (c) risk seeking for gains if probabilities are low (e.g., lottery tickets), (d) risk aversion for losses if probabilities are low (e.g., buying insurance), (e) risk seeking for losses if probabilities are high, (f) the certainty effect, (g) the possibility effect, and (h) intransitivities. The authors test how accurately the heuristic predicts people's choices, compared with previously proposed heuristics and 3 modifications of expected utility theory: security-potential/aspiration theory, transfer-of-attention-exchange model, and cumulative prospect theory.  相似文献   
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